Franken is wrapping up a several-day trip to Washington, which included inauguration-related activities, a military hospital visit and a high-dollar fund-raiser. Franken returns to Minnesota Thursday, spokeswoman Jess McIntosh said.

The candidates' attorneys this afternoon will go before the three-judge panel considering Franken's request to dismiss the Coleman election challenge. Franken attorneys argue the judges do not have jurisdiction over the issues raised in Coleman's filing. They also claim Coleman's challenge is too vague.

Franken emerged from a statewide ballot recount with 225 more votes out of nearly 2.9 million cast. Coleman led on election night.

Coleman, a Republican seeking a second Senate term, is challenging the recount results because he said some valid votes were not counted while others were counted twice.

If the three judges decide not to dismiss the case, they will preside over an election trial beginning Monday.

Coleman's attorneys have stressed that several ballot issues should be examined closely in the trial because of flaws and irregularities on Election Day and during the recount.

Absentee ballots could loom large. An estimated 12,000 absentee ballots were rejected in the election, but some were improperly rejected for reasons not set out in state law.

More than 900 of those were opened and counted during the recount, but Coleman attorney Fritz Knaak said the campaign wants all 12,000 reviewed for possible counting during the trial.

The campaigns have spent weeks preparing for the court proceedings, which could take weeks or longer. Coleman's campaign sought lists of Election Day poll workers and precinct voter rolls and planned to interview local election officials leading up to the trial's start.

Election contest proceedings will take place in a Minnesota Judicial Building courtroom, near the Capitol. The three district court judges appointed to preside over the case are Elizabeth Hayden of Stearns County, Kurt Marben of Pennington County and Denise Reilly of Hennepin County.

A separate lawsuit filed by Franken remains before the Minnesota Supreme Court. Franken wants the justices to order that he be given a signed election certificate, even as the election contest remains unresolved. The election certificate, which Gov. Tim Pawlenty and Secretary of State Mark Ritchie refused to sign before the election lawsuit plays out, could allow Franken to be seated in the Senate. The high court set a Feb. 5 hearing on that request.

The campaign claims the failure to issue an election certificate "impermissibly encroaches on the Senate's authority" to seat its members.

"On Nov. 4, the citizens of Minnesota elected a senator," Franken attorney David Lillehaug wrote in a Tuesday filing. "Over two months have since passed ... Yet to this day, only one senator sits from Minnesota."